So thank you for the introduction, and my name is Mayu Tanabe from Showa University Koto Teosho Hospital. I'm working with Dr. Haruhi Inoue, and I'm going to show you a case, a chronic ESD case. And actually, after those beautiful presentation, this is a case with an SMD invasion case. So this is a protruding lesion located in the sigmoid column. Initially, after preoperative investigation, we suspected it to be a lesion invading to a deep submucosal layer. But due to patient old age and the presence of multiple comorbidities, we proceeded with ESD. And after mucosal incision, we entered the submucosal layer. And however, there are findings of muscle layer retraction sign, and making it difficult to identify the incision line. And to address this, we identified a submucosal layer on both sides of the muscle layer retraction, and gradually determined the correct incision line. So the width of the muscle layer retraction gradually narrows. We proceeded with the incision slowly while maintaining a clear field of view using the rotor pressure method. But however, we encountered unexpected bleeding when we were almost done. So we were, I was careless at this moment. So we attempted to locate the bleeding point using RDI, you know, reducing psychological stress. Yeah. But hemostasis with a knife was ineffective. So we decided to use a coragrasper. Here we carefully performed hemostasis using coragrasper, but you can see this small hole for perforation. I think this was a penetrating artery from the muscle layer. So we then, after managing to achieve hemostasis, we promptly closed the perforation using clips. And after closing the small perforation site, we continued with the remaining dissection. And ultimately, an incomplete resection of the lesion was achieved. So after resection, this is a defect site. And as a precaution, we closed the closure on the defect site using an additional clip. I carefully grabbed the muscle layer like this with truoclip. But fortunately, the patient did not experience postoperative abdominal pain, and the increase in inflammatory marker was minimal, and the patient was discharged home as scheduled. The final pathological diagnosis confirmed the lesion as PT1B, but the resection margin was negative, and there were no lymphobascular invasion. Thank you very much. Wonderful case. So what did you do after the complete resection of this tumor? You mean the patient? For the patient? Yeah. If we did additional surgery? I mean, yes. Actually, to be honest, we asked anesthesiologist to perform surgery, and he underwent stigmoidectomy, and there were no lymph node metastasis. Thank you. Is there any question or comment? Muscle traction sign in the colon is the most challenging situation to endoscopic resection. But even with severe fibrosis, we can nicely visualize the fibrotic area by utilizing the water pressure method. But as you showed in this video, sudden breathing is the major problem for the water pressure method. But as you've shown us, RDI is quite effective to visualize the breathing point and also reduce the psychological stress. I really like the RDI model. So I set the pattern, shortcut pattern for RDI during GSD. I have one question. So the RDI is very promising in my view that you can see the deep-seated vessel within semicosa before you cut it. Would you think about activating RDI while you're doing semicosal dissection? Yes. I think we can do that during. Would that be helpful? Yes. I think that will be helpful. Sometimes I do that, but not all the time. And the second question is the perforation. The Australian group just proposed those classifications. I think it's very important to just really evaluate to see if there's an intact cirrhosis or not. Could you explain to the audience and the participants how would you evaluate? When do you think it's cirrhosis disrupted? Through perforation versus near perforation. Okay. Actually, I think this case was a perforation. We didn't see any fat or any covered cirrhosis through the tiny hole. And it depends on the region, where the region is, because if it's posterior, like if it's the region located in the ascending colon, posterior wall, there should be covered outside tissue. But this is a sigmoid colon. Sometimes we can see the mesentery. The border? Yes. I think it can be visualized by thoroughly see the defect site. Yes, please. Can I ask a follow-up question on the perforation? So when you encounter a perforation while performing an ESD, I guess you have two options, right? One is to close the perforation immediately or finish your ESD and then go back and close the perforation. What makes you decide to do one versus the other option? I usually try to close the defect as soon as I found it. Because I'm a big fan of water pressure method, so if I continue on without closing the defect and continue on water pressure method, there will be a big trouble. But sometimes it's difficult to close the defect immediately after it because you have some submucosal layer left. So I will quickly continue on submucosal dissection near the defect and then immediately close. So I will choose to immediately close the defect as soon as I found it. Usually it is necessary to have enough space to apply endoclip. Therefore, we should dissect a little bit more around the perforation site. Then we can easily capture the both edge using short-size grip. You know, sometimes you keep dissecting and try to come back to the perforation. It just gets obscured. All these muscles kind of come together and difficult to find the location too, right? So it's a fine balance between how long you're going to open up. Yes, I agree. I have a question, a comment. You used the ordinary transparent fluid. I think in the water pressure method, the magnification effect, you can see the lower view. So you should use the device longer. I would like to use the tapered tip. And in this case, severe fibrosis, it is very difficult to go into the narrow space. So I recommend the tapered tip fluid. The second point is the differentiation between the fibrotic change and the muscle layer. We can read the direction. So usually the muscle layer goes in a circular direction. So not only the color, but also the direction, we can differentiate the fibrotic tissue and muscle layer. Thank you for your comment. Best way to clear the difficulty with muscle traction or severe fibrosis, we should dissect both sides first. Then visualize the remaining fibrotic area or muscle traction area. Then connect both sides. That is the best way to avoid risky situation. I think Dr. Toyonaga had lots of experience doing such a difficult procedure. What is your technical tip to avoid risky situation? First of all, I start from the PCM, definitely. And I create the space you mentioned, both side of the muscle interaction. And also from now on, I'm observing the muscle bundle line from the more lower side. Then I'm using tapping technique. I dissect the submucosal fiber just on the surface of the muscle. Then it can be something like throat. So after that, the mostly fibrotic area could be minimized. Then, of course, in the colon, just surface of the muscle should be traced. But in the rectum, we will come a little bit deeper to the muscle layer because the muscle layer is much thinner than colon. That's my technical point of view. I wanted to ask the faculties also about this. When you cut these fibrosis, do you use a cut current or coagulation? I'm using the short duration. Because it's difficult to identify the vessels within these fibrosis. Dr. Toyonaga's answer is short duration, end cut. Just tap, tap, and end cut. Do you, Dr. Toyonaga, or anybody, do you recommend a needle end? Needle end dissection? Needle end dissection, not possible in flash knife because the total inside tube. Needle end dissection would be for the draw knife or the tech knife, something like that. But when you use the flash knife, I'm observing the tip of the ball. And just slightly touch or just close to the fibrotic target and spark. The tapping technique, it works very well. It means not hooking the large amount of tissue when you cut through the fibrotic area. Honestly speaking, needle end technique is totally blind fashion. So you don't see the spark on the tip of the knife. But at tapping technique, we can see every single stroke. So I guess more precise dissection can be done even using the dual knife, needle out technique. Not touch too much, gentle touch. Just coming close is plenty enough. Okay, thank you very much. Thank you. Let's move on to the next.

chronic ESD

SMD invasion

sigmoid colon

muscle layer retraction signs

submucosal layers